Treat it like a business and not as a hobby, and you should do fine. Plan plan plan! Figure out who your target customers are, how to reach them, and what their interests are. Most importantly, create a genuine connection with them so that they know you are sincere. Always find ways to stay ahead of your competitiors and keep your business and designs fresh. Give your customers a reason to keep coming back for more.
And like Heidi said, research EVERYTHING!
